Få SUM af salg i flere år i kolonner

Ændrer bare et af svarene for at få kunder uden ordrer -

Select c.name, 
   Sum(Case When o.year == 2008 Then price Else 0 End) cy2008,
   Sum(Case When o.year == 2009 Then price Else 0 End) cy2009,
   Sum(Case When o.year == 2010 Then price Else 0 End) cy2010
From Customers c left outer join 
     Orders o on o.customer_id = c.customer_id
Group By c.name